In October 2017, astronomer Robert Weryk saw a mysterious stick-shaped object with a faint reddish tint, located just 21 million miles from Earth (a relatively small distance in the vastness of space). He was using the Pan-STARRS1 telescope at the Haleakala Observatory in Hawaii, US, which looks for “near Earth” objects. This unexpected visitor was named ‘Oumuamua (say “oh-mu-ah-muah”), a Hawaiian word meaning “a messenger from afar arriving first”. It was the first known object from another solar system to visit our solar system, and the discovery raised many questions. Was this mysterious rock an asteroid, a comet, or perhaps something more extraordinary, like an alien spaceship?
image [https://cdn.magzter.com/1642519507/1726203999/articles/EEC4wtNUx1726212012857/0692722149.jpg]
A race against time Scientists only had a few weeks to track ‘Oumuamua as it went in the direction of Pegasus (a constellation) before heading towards the orbit of Neptune. After this, it would vanish from Earth’s view forever. Astronomers briefly considered the possibility that 'Oumuamua was an asteroid. However, it didn’t behave the way asteroids usually do. In fact, the more scientists studied ‘Oumuamua the stranger it became. Let’s start with its shape. At around 400 metres long, ‘Oumuamua is 10 times longer than it is wide. No other known objects in the solar system are more than three times longer than they are wide. ‘Oumuamua also moved like a comet, which means it accelerated as it moved past the Sun. Comets usually do this because the Sun heats their icy surface, releasing melted gases. The gases push the comets faster, causing them to display a bright tail across the night sky. ‘Oumuamua had no bright tail and it was moving at shocking speed – 196,000 miles per hour – faster than any known comet. This led scientists at the Harvard Smithsonian Center for Astrophysics to suggest that ‘Oumuamua was a probe sent to Earth by an alien civilisation. In 2017, the Breakthrough Listen Initiative used radio telescopes to listen for signals of alien life, b...
image [https://cdn.magzter.com/1642519507/1726203999/articles/EEC4wtNUx1726212012857/0692722149.jpg]
A race against time Scientists only had a few weeks to track ‘Oumuamua as it went in the direction of Pegasus (a constellation) before heading towards the orbit of Neptune. After this, it would vanish from Earth’s view forever. Astronomers briefly considered the possibility that 'Oumuamua was an asteroid. However, it didn’t behave the way asteroids usually do. In fact, the more scientists studied ‘Oumuamua the stranger it became. Let’s start with its shape. At around 400 metres long, ‘Oumuamua is 10 times longer than it is wide. No other known objects in the solar system are more than three times longer than they are wide. ‘Oumuamua also moved like a comet, which means it accelerated as it moved past the Sun. Comets usually do this because the Sun heats their icy surface, releasing melted gases. The gases push the comets faster, causing them to display a bright tail across the night sky. ‘Oumuamua had no bright tail and it was moving at shocking speed – 196,000 miles per hour – faster than any known comet. This led scientists at the Harvard Smithsonian Center for Astrophysics to suggest that ‘Oumuamua was a probe sent to Earth by an alien civilisation. In 2017, the Breakthrough Listen Initiative used radio telescopes to listen for signals of alien life, b...
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The Week Junior Science+nature Uk (Digital) - 1 Issue, Issue 79